Door and doorway and threshold therefor for air-tight inclosures.



No. 784,904. PATENTED MAR. 14, 1905.. I s. P. STEVENSON. DOOR AND DOORWAY AND THRESHOLD THEREFOR FOR AIR TIGHT INGLOSURES.

APPLICATION FILED MAR. 8, 1901.

INVENTOR .f/w f wanaq YMM UNITED STATES Patented March 14, 1905.

PATENT OFFICE.

DOOR AND DOORWAY AND THRESHOLD THEREFOR FOR AIR-TIGHT INCLOSURES.

SPECIFICATION forming part of Letters Patent No. 784,904, dated March 14, 1905.

Application filed March 8, 1901. Serial No. 50,359.

To all wlwm it may concern:

Be it known that I, SAMUEL PRICE STEVEN- SON, a citizen of the United States, residing in the city of Chester, county of Delaware, and State of Pennsylvania, have invented a new and useful Improvement for Doors and Doorways and Thresholds Therefor for Air-Tight Inclosures and Apartments, of which the fol lowing is a specification.

This invention relates to doors required to close air-tight apartments, such as are used for refrigerating and dry-storage purposes, and particularly to the closure of such doors at the lower end to the floor-entrance; and to this end it consists in a sill or threshold at the floor or bottom end of the door-frame attached to and forming part of the door-frame and extending forwardly a distance in front of said door-frame, the extending portion being beveled downwardly a portion of its thickness without a perishable feather-edge and continuing the floor into the doorway practically unbroken and free from jolting obstructions, and a special construction and arrangement of packings to insure air tight fitting when closed with a minimum of wear on the packing in opening and closing.

The construction of this invention is shown in the accompanying drawings, in which Figure 1 shows a vertical section of the lower portion of the doorand doorway in closed position with this invention applied thereto. Fig. 2 shows a side elevation thereof in closed position with the near door-post omitted. Fig. 3 shows the same in open position.

Referring to the drawings, (0 represents the face or front of the door; I) b, the vertical strips or stiles; 0, the inner sheathing; (l, the lower horizontal frame of the door.

a is the floor of the refrigerating-chamber or air tight apartment, and an inclined threshold-approach to the door.

The stiles b are shorter than the door, and the lower rail (5 is made with the lower edge or surface parallel with the floor e and flush with the lower ends of the stiles b b. The lower edge of the face a of the door is parallel with the floor e and considerably lower than the lower surface of the rail (Z. g is a strip parallel with the rail (Z, secured to the lower end of the stiles b b and provided with packings It A, which are secured to the inner and outer surfaces of the strip g and are clamped between the lower parts of the face a and the strip 71, secured to the strip 9 between the packings [L h. floor in front of the door is downwardly inclined, so as to cleartlie packings it h when the door is opened, and as it closes compresses the packings 7t 7t upwardly, so as to react when closed into intimate contact with the floor 0. level portion of the floor 6 within the doorframe are made integrally and of such thickness as to form a firm and substantial portion of the floor approaching the doorway. By the inclined form of threshold I relieve the packings 7t it of wear in the open position of the door and avoid any abrupt angles or step in the entrance to the doorway. The packings 7b 7b are formed of elastic felt folded, as shown in Fig. 1, so as to present the bent portions to contact with the floor 0. The front packing it extends across the full width of the doorway, and the inner or rear packing 7a is returned at the ends it, so as to meet the ends of the front packing 7t. and packings it it are readily adjustable in height by means of the mode of attachment of the strip 9 to the stiles b I) ofthe door, as above described.

A hair felt of elastic properties hasbeen found the best material for forming the packings h It on account of retaining elasticity and applying closely to the floor with slight wear, and consequently best durability.

hen the door is opened, the packings it h clear the threshold f. hen the door closes, the inclined surface of the threshold compresses the packing into close contact with the floor and forms an air-tight seal between the lower end of the door and the floor in the doorway.

By attaching the packings I, /t to the strip g and securing the strip 9 to the lower ends of the stiles Z) 5 I avoid the variations in the height of the packing which would be incident to the swelling and contracting of the lower rail of the door from hygrometric The threshold f or The inclined part or threshold f and i The strip g changes and have an easy means of adjusting the height of the packing to conform to the floor.

Having described my invention, what I claim is 1. In an air-tight door and frame therefor a sill and threshold having the front portion of said sill beyond the front of said door-frame beveled downwardly with a thick front edge adapted to be let into the floor as shown, and described in combination with a strip adjustably secured to the bottom of the door, and folded packings 7L and h secured to the front and rear surfaces of said strip, arranged to oppose the folded edges of said packings to the horizontal surface of said sill within the doorway and clear the inclined forwardly-extended portion of said sill when the door is in open position as set forth.

2. An article of manufacture and sale, comprising a door and door-frame and a sill and threshold therefor, said door having a flexible packing at its lower end and being hinged to the frame to swing forwardly over the threshold, and the sill and threshold being formed integrally with a horizontal upper surface between the door-jam bs and under the door when closed, whereby a rest for said packing is afforded upon such horizontal surface, and having a downwardly-inclined upper surface in front of the door with a thick front edge adapted to be embedded in a floor, as set forth and described.

3. A packing for the lower ends of air-tight doors consisting of a front packing of folded flexible material, a strip attached thereto adapted to be secured to the lower end of the door in combination with an inner or rear packing of folded flexible material secured to said strip, and having the ends returned to meet the front packing as described and shown.

S. PRICE STEVENSON.

\Vitnesses:

G120. WV. SCHREINER, C. R. MORGAN. 

